The invention relates to a railway vehicle door, intended for a door opening with steps, on which there are provided a platform and a movable threshold above the steps so as to permit disembarking onto a railway platform situated higher than the steps.
Such railway vehicle doors are already known, having a platform and threshold arranged above steps.
The document U.S. 5,070,794 describes a railway vehicle door for a door opening to which the passengers gain access by means of a set of steps arranged inside the vehicle. This door comprises two leaves, bottom and top, sliding with respect to each other, and connected by locking means. The door is mounted so as to slide between a closed position and an open position. A platform is fixed so as to be articulated on an axis substantially perpendicular to the door and is situated substantially in the horizontal plane of the top of the steps, the said platform being able to be moved from a free retracted position with respect to the said horizontal plane and a position of use in which it is situated in the said horizontal plane. A threshold member projects with respect to the external face of the door in order to fill in at least part of the space lying between the edge of the platform, in the position of use, and the edge of the railway platform. This threshold member is an integral part of the bottom leaf.
The aim of the invention is to produce a door having a simplified structure compared with the door described above.
To that end, the invention concerns a railway vehicle door consisting of a single leaf having a threshold member making it possible to reduce the space between the platform and the railway platform, when the platform is in the position of use.
The door according to the invention thus has the same advantages as the doors used in the prior art.
The invention is characterised in that the door consists of a single leaf and in that means are provided for controlling the unlocking of the threshold member with respect to the door, when the platform is in the position of use and the door opens, so that this threshold member remains in place opposite said edge of the platform in the position of use and the edge of the railway platform.
According to a preferred embodiment of the invention, the threshold member is partly embedded in a recess formed in the door.
The vehicle body comprises, close to the edge of the door opening opposite to the direction of opening of the door, means for supporting the end of the threshold member, when the door is open.
These means for supporting the end of the threshold element comprise, for example, rollers carried by the said end of the threshold member and abutment surfaces receiving the said rollers fixed to the vehicle body.
In a first variant of the preferred embodiment, the guidance means between the threshold member and the door comprise:
a rail fixed to the threshold member extending in the longitudinal direction of the said threshold member and projecting from the end of this member in the direction of opening of the door,
and a slide on which the rail slides, the slide being fixed to the body and having a length at least equal to the length of the threshold member.
In a second variant of the preferred embodiment, the guidance means between the threshold member and the door comprise:
a rail fixed to the door, extending in the longitudinal direction of the threshold member and projecting from the end of the door on the same side as the direction of opening of the latter with a length at least equal to the length of the threshold member,
and a slide fixed to the threshold member on which the rail slides, the length of the slide being substantially identical to that of the rail when the door is closed.
In a third variant of the preferred embodiment, the guidance means between the threshold member and the door comprise
a rail fixed to the threshold member, extending in the longitudinal direction of the threshold member and slightly projecting from the end of the door on the same side as the direction of opening of the latter
an internal slide fixed to the door
an intermediate slide in which the internal slide slides and which slides in the rail.
This last variant permits to reduce the dimensions of the guidance means.
In the two variants, when the platform is in the position of use and the door opens, the threshold member remains in place opposite the said edge of the platform in the position of use and the edge of the railway platform.
Other particularities and advantages of the invention will also emerge from the following description.